1. Field of the Invention
The field of the invention relates to prepping catheters, and more particularly to flushing catheters.
2. Background
Catheters are commonly used to access the interior of a patient's body. The distal end of the catheter may be equipped with a medical device, e.g., an ultrasound transducer, a light imaging device, a balloon, or the like, for performing medical procedures in the body. Alternatively or in addition, the distal end of the catheter may have an opening for releasing therapeutic agents in the body. To access a treatment site in the body, the catheter is advanced through a body lumen, e.g., blood vessel, to the treatment site.
Catheters include an elongated catheter body having one or more lumens extending through the catheter body. A medical device, e.g., an ultrasound transducer, may be slideable received within the catheter body lumen. Prior to use in a medical procedure, the catheter body lumen is flushed with a flushing solution, such as saline or sterile water. The solution displaces the air in the catheter lumen, thereby reducing the risk of air being accidentally released in the body from the catheter. In addition, for a catheter comprising an ultrasound transducer, the solution provides an acoustic coupling media for coupling ultrasound energy between the ultrasound transducer and the surrounding body.
Prior to use, a physician or nurse removes the catheter from a sealed package in a sterile environment. The physician then preps the catheter for insertion into the patient's body. The prepping procedure includes flushing the catheter lumen with flushing solution, e.g., saline or sterile water, to remove air from the catheter lumen. This may be done, e.g., by inserting a syringe 75 filled with the flushing solution into a valve 70 coupled to the proximal end of the catheter 65 and injecting the solution into the catheter lumen through the valve 70, as illustrated in FIG. 23.
Even though the catheter lumen is flushed with the flushing solution, air bubbles may remain trapped in the catheter. To address this problem, several techniques have been developed to remove air bubbles from the catheter. One technique is to hold the catheter at a distance from its distal tip and swirl the catheter. Swirling the catheter produces a centrifugal force that pulls the solution towards the distal end of the catheter, displacing trapped air bubbles. A problem with this technique is that the physician or nurse swirling the catheter may accidentally strike a nearby object, e.g., medical equipment or table, with the catheter, damaging the catheter.
Another technique is to provide a self-sealing septum at the distal end of the catheter. In this technique, flushing solution is injected into the catheter lumen from the distal end rather than the proximal end of the catheter. A syringe filled with the flushing solution is inserted into the distal end of the catheter through the self-sealing septum and the solution is injected into the catheter lumen. The syringe is then pulled out of the septum, and the septum seals itself. A problem with this technique is that the physician or nurse inserting the syringe into the distal end of the catheter may accidentally puncture the side wall of the catheter or damage a medical device in the catheter with the needle tip of the syringe.
Therefore, there is a need for an improved system and method for flushing catheters.